Protective effects of pistachio oil (Pistacia vera) on follicle development in C57BL/6J mice model undergoing chronic unpredictable mild stress

Background: Women are sensitized to stress-related psychiatric disorders, such as depression and anxiety. Several studies have shown that follicular development and ovarian reserve are reduced after chronic stress. Objectives: In this experimental study, the effect of oral consumption of pistachio oil was evaluated on mice models undergoing chronic unprintable mild stress. Material and Methods: 6–8-week-old female C57BL/6J mice were randomly divided into 4 groups: one control and three experimental groups (n= 8). Animals in experimental groups (I, II, and III groups) were exposed to a variety of chronic unpredictable stress for 4 weeks. Then, the mice in I and II groups were fed orally 1 and 4 ml/kg/day pistachio oil for 4 weeks, respectively. Animals in the III and control groups received tab water. Forced swimming test (FST), sucrose preference test (SPT), and tail suspension test (TST) were performed to evaluate behavioral despair and hedonic level in mice. Their ovaries were analyzed for the number and diameter of primordial, primary, secondary, and antral follicles. Results: FST showed depressive-like behavior to be increased in stress groups compared with the control. According to SPT, greater data deviation was observed in the control mice compared to the experimental groups (P = 0.036). Follicle cell numbers showed a significant decrease in the I and III groups compared to the control (p = 0.034). In addition, there was a remarkable decreasing trend in the diameter of secondary and antral follicles in the I and III groups (p = 0.039). Conclusion: This study demonstrates that pistachio has protective impacts on unpredictable chronic mild stress in the mice model. Therefore, pistachio could be a potential medical supplement for improving follicular development and ovarian reserve.